Please be aware that Kuala Lumpur has multiple airports and that these results are for all airports serving the city.
The best month to fly between Kuala Lumpur and Langkawi is May and the most expensive month to fly is September. (Average prices, based on 65746 datapoints.)
The cheapest airline flying from Kuala Lumpur to Langkawi is AirAsia. They are 45% cheaper than MasWings. (Average prices, based on 65769 datapoints.)